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"Das U-Boot" Source Tree
include: Add generic bitops headers
Use the generic bitops header files from the kernel.
Imported from kernel 4.2.3.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
authored by
Fabio Estevam
and committed by
Tom Rini
77c8554e
f598e7a9
+163
+43
include/asm-generic/bitops/__ffs.h
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include/asm-generic/bitops/__ffs.h
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#ifndef _ASM_GENERIC_BITOPS___FFS_H_
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#define _ASM_GENERIC_BITOPS___FFS_H_
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#include <asm/types.h>
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/**
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* __ffs - find first bit in word.
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* @word: The word to search
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*
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* Undefined if no bit exists, so code should check against 0 first.
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*/
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static __always_inline unsigned long __ffs(unsigned long word)
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{
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int num = 0;
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#if BITS_PER_LONG == 64
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if ((word & 0xffffffff) == 0) {
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num += 32;
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word >>= 32;
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}
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#endif
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if ((word & 0xffff) == 0) {
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num += 16;
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word >>= 16;
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}
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if ((word & 0xff) == 0) {
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num += 8;
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word >>= 8;
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}
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if ((word & 0xf) == 0) {
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num += 4;
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word >>= 4;
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}
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if ((word & 0x3) == 0) {
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num += 2;
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word >>= 2;
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}
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if ((word & 0x1) == 0)
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num += 1;
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return num;
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}
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#endif /* _ASM_GENERIC_BITOPS___FFS_H_ */
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include/asm-generic/bitops/__fls.h
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include/asm-generic/bitops/__fls.h
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#ifndef _ASM_GENERIC_BITOPS___FLS_H_
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#define _ASM_GENERIC_BITOPS___FLS_H_
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#include <asm/types.h>
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/**
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* __fls - find last (most-significant) set bit in a long word
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* @word: the word to search
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*
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* Undefined if no set bit exists, so code should check against 0 first.
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*/
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static __always_inline unsigned long __fls(unsigned long word)
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{
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int num = BITS_PER_LONG - 1;
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#if BITS_PER_LONG == 64
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if (!(word & (~0ul << 32))) {
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num -= 32;
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word <<= 32;
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}
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#endif
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if (!(word & (~0ul << (BITS_PER_LONG-16)))) {
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num -= 16;
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word <<= 16;
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}
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if (!(word & (~0ul << (BITS_PER_LONG-8)))) {
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num -= 8;
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word <<= 8;
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}
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if (!(word & (~0ul << (BITS_PER_LONG-4)))) {
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num -= 4;
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word <<= 4;
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}
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if (!(word & (~0ul << (BITS_PER_LONG-2)))) {
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num -= 2;
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word <<= 2;
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}
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if (!(word & (~0ul << (BITS_PER_LONG-1))))
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num -= 1;
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return num;
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}
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#endif /* _ASM_GENERIC_BITOPS___FLS_H_ */
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include/asm-generic/bitops/fls.h
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include/asm-generic/bitops/fls.h
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#ifndef _ASM_GENERIC_BITOPS_FLS_H_
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#define _ASM_GENERIC_BITOPS_FLS_H_
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/**
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* fls - find last (most-significant) bit set
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* @x: the word to search
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*
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* This is defined the same way as ffs.
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* Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
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*/
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static __always_inline int fls(int x)
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{
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int r = 32;
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if (!x)
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return 0;
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if (!(x & 0xffff0000u)) {
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x <<= 16;
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r -= 16;
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}
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if (!(x & 0xff000000u)) {
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x <<= 8;
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r -= 8;
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}
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if (!(x & 0xf0000000u)) {
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x <<= 4;
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r -= 4;
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}
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if (!(x & 0xc0000000u)) {
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x <<= 2;
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r -= 2;
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}
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if (!(x & 0x80000000u)) {
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x <<= 1;
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r -= 1;
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}
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return r;
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}
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#endif /* _ASM_GENERIC_BITOPS_FLS_H_ */
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include/asm-generic/bitops/fls64.h
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include/asm-generic/bitops/fls64.h
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#ifndef _ASM_GENERIC_BITOPS_FLS64_H_
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#define _ASM_GENERIC_BITOPS_FLS64_H_
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#include <asm/types.h>
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/**
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* fls64 - find last set bit in a 64-bit word
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* @x: the word to search
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*
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* This is defined in a similar way as the libc and compiler builtin
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* ffsll, but returns the position of the most significant set bit.
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*
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* fls64(value) returns 0 if value is 0 or the position of the last
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* set bit if value is nonzero. The last (most significant) bit is
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* at position 64.
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*/
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#if BITS_PER_LONG == 32
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static __always_inline int fls64(__u64 x)
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{
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__u32 h = x >> 32;
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if (h)
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return fls(h) + 32;
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return fls(x);
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}
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#elif BITS_PER_LONG == 64
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static __always_inline int fls64(__u64 x)
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{
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if (x == 0)
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return 0;
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return __fls(x) + 1;
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}
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#else
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#error BITS_PER_LONG not 32 or 64
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#endif
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#endif /* _ASM_GENERIC_BITOPS_FLS64_H_ */